public class demo2 {

    public static void main(String[] args) {
        Object o1 = new Object();
        Object o2 = new Object();

        Thread t1 = new Thread(()->{
           synchronized (o1){
               try {
                   Thread.sleep(1000);
               } catch (InterruptedException e) {
                   throw new RuntimeException(e);
               }
               synchronized (o2){
                   System.out.println("执行 t1 线程");
               }
           }
        });

        Thread t2 = new Thread(()->{
           synchronized (o2){
               try {
                   Thread.sleep(1000);
               } catch (InterruptedException e) {
                   throw new RuntimeException(e);
               }
               synchronized (o1){
                   System.out.println("执行 t2 线程");
               }
           }
        });

        t1.start();
        t2.start();
    }
}
